$($Weighted average cost of capital$)$ Crypton Electronics has a capital structure consisting of $37$ percent common stock and $63$ percent debt. A debt issue of $$1,000$ par value, $5\mathrm{.}7$ percent bonds that mature in $15$ years and pay annual interest will sell for $$971.$ Common stock of the firm is currently selling for $$29\mathrm{.}59$ per share and the firm expects to pay a $$2\mathrm{.}15$ dividend next year. Dividends have grown at the rate of $4\mathrm{.}7$ percent per year and are expected to continue to do so for the foreseeable future. What is Crypton's cost of capital where the firm's tax rate is $30$ percent?

a$.$ The after$-$tax cost of debt is

$\%.($Round to two decimal places.$)$